Micrometer-fred for grinding-machines.



0'. G. TREFETHEN.

MIGROMETEB. FEED FOR GRINDING MACHINES.

APPLICATION FILED MAR. 2, 190a. 91 5 128, Patented Mar. 16, 1909.

2 SHEETS-SHEET l.

5 F'IGE.

INVENTEJH.

ATTDWNEY G. G. TREFETHEN.

' MIOEOMETER FEED FOR GRINDING MACHINES.

APPLICATION FILED HA3. 2, 1908.

915,128. Patented Mar. 16,1909.

2 SHEETS-SHEET 2.

. Fig. 2, a plan view of nnrrnn s r nsgrgpnnr OFFICE.

CHARLES G. TREFETHEN, OF PROVIDENCE, FHODE ISLAND, ASSIGNOR TO ATLAS MACHINE TOOL COMPANY, A CORPORATION OF MAINE.

MIGROMETER-FEED FOR GRINDING-MA HINE$.

fipecification of Letters Eatent,

Patented March 16, 1909.

Application filed March 2, 1908. Serial No. M8386.

To all whom it may concern: I

Be it known that I, CnAnLEs G. TREFE- THEN, a citizenof the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Micrometer-Feeds for Grinding-Machines, of which the following is a specification.

My invention relates to miorometric feeds for grinding machines whereby the grinding wheel and slide are advanced toward the article .to be ground; and is primarily directed to the actuating mechanism for the reciprocating pawl, and to the construction and operation of the carrier.

' The objects ofmy invention are those commonly sought in this class of structures; but more particularly to provide means for varying the intensity or depth of the feed or advance of the grinding wheel at each stroke of the reciprocating platen or bed'plate; to lessen th. wear on the disk teeth; and to make the action of the reciprocating pawl upon the disk certain and positive.

A further object is to provide a simple, accurate, and effective device for manually operating the micrometric feed. Also to improve the means for automatically advancing the toothed disk, and the means for adjusting the advancing means.

In the drawings which constitute a part of these specifications, Figure 1 is a front elevation of a portion of the frameof a grinding machine equipped with my novel feed; a portion of the band wheel being broken away. the same. .Fig. 3, a section on line a: a of Fig. 1. Fig. l, a rear elevation of the carrier. Fig. 5, a detail view of the pawl, and Fig. 6, a section on line 1 y of Fig. 5.

Like reference characters indicate like parts throughout the views.

In the drawings, is the frame, 2 the platen, 3 the, adjustable stops. upon the platen, i the screw spindle, 1 the spindle bearing, 5 the hand wheel of the" spindle, 6 the disk fixed to the spindle and provided with ratchet teeth, {7 ,8 the rock shaft, and 9 the operating or'rock lever, and 10 the lever handle, of an ordinary grinding ma chine. The grinding Wheel slide and its con nection with the spindle, 4, are of the usual construction Pivoted at one end upon a stud, 11, in the 5. fixed in the carrier.

frame below the lever, 9, is a horizontal lever,-

14, in which are mounted vertical adjusting screws, 15 and 16, respectively. Abovethe lever, 12, is a stud, 17 upon which IS a hub,

legs, 19, 20 and 21, equidistant from'eacl other. A link, 22, connects the lower end of the lever, 9, with the vertical leg, 19'; and the legs, 20'and 21, normally contact with the flat upper surfaces of the screws, 15 and 16, respectively. A link, 24, connects the free end of the lever, 12, with the intermediate portion of an arm, 25, pivoted to the screw spindle, 4, inthe rearof the disk, 6. Pivoted to a pin, 26, in the end of the arm, 25, 1s a pawl, 27, adapted to-engage the ratchet teeth, 7'." To facilitate engagement and disengagement of the pawl, cavities 2-8 and 29 are provided in the pawl face adapted to re ceive the curved end of 'a pin, 30, slidably mounted in the arm, 25, and pressed by a spring, 31, which is retained by a screw, 32, as shown in Fig. 6, A helical spring, 34:, has one end fixed to a pin, 34, in the machine frame above the lever, 12, and its other end connected to the latter, whereby the screws, 15 and 16, are normally pressed against the arms, 20 and 21. I

- The mechanism employed in actuating the disk, 6, when the latter is operatedby power has been described. The means for manually operating the disk comprises a carrier, 35, fixed to or integral with the free end of an arm, 36, which is pivotally mounted upon the spindle, 4, adjacent the front face of the disk, 6. 'The carriage overhangs the periphery of the disk, and is, with the arm, 36, independent of the latter. A shield, 37, is fixed to one end of the carrier. A hand lever, 38, is pivoted intermediate its length upon a pin, 39,

against the under face ofthe lever by a rivet, 10, passing through the outer ends of each. The inner end of the arm, 40, terminates in a downwardly inclined finger, 41. An adjusting screw, 43, is mounted in the lever, 38, and .presses"downwardly against the arm, 40, to force the finger, 41, into engagement with the teeth of the disk, 6. The inner end of the rod is downwardly pressed by a spring, 44,

The carrier is also proslot, 46, adapted to rel vided with a vertical 12, provided intermediate its length with' two interspaced threaded openings, 13 and 18, provided with three radially disposed in the carrier. A spring arm, 40, is held oted to the'frame, 1.

' lows: T e dogs, 3, upon the reciprocating platen vibrate the lever, 9, which through the link, 22, alternately elevates and lowers the arms, 20, 21, thereby vibrating the lever, 12, and, through link, 24, the arm, 25, whereby the pawl, 27, moves the disk, 6, and its' screw spindle one or more teeth. Thus intermittent rotary motion is imparted to the disk and spindle. By elevating or depressing the screws, 15 and 16, relatively to each other, the pawl arm, 25, and disk, 6, will both be advanced different distances at each successive reciprocation of the platen, 2, whereby a fine and coarse feed will be alternately afiorded. During the operation of the hand feed, the pawl, 27 is swung out of the path of the teeth, 7 whereby the pin, 30, is forced out of the cavity, 28, and enters the cavity, 29, thus maintaining-the pawl out of the path of the ratchet teeth. The hand feed is operated by initially turning the screw, 43, to del press the finger, 41, into the Ipath of the disk teeth, and then alternately e evating anddepressing the outer end of the hand lever. It is often desirable to lock the carrier, 35, or arm, 36, against movement relatively to the ratchet disk. This end is attained by dropping the hooked bar, 48, into the slot, 46, of the carrier. Over-rotation of the disk, 6, may be prevented by pressing the friction plate, 50, against the disk by means of the spring, 51, and screw, 52. By mounting the arm, 25 upon the spindle or concentric therewith a more positive action upon the disk, 6 is secured, and without injury to the teeth, 7, by the pawl, 27. It will be observed that the adjustment of the screws, 13 and 14, not only governs the degree of rotation of the toothed disk, but regulates also therelative difference in the advance of the diskin each successive vibration.

What I claim is,

1. In a micrometric feed for a grinding machine the combination with the screw s indle and disk, of means for advancing the isk a different distance at each successive impulse.

2. In a micrometric feed for a grinding machine the combination with the screw spindle. and disk provided with ratchet teeth, of a pawl enga ing the ratchet teeth, and means for impe ing the pawl a different distance at each successive im ulse.

3. In a micrometric fee for a grinding machine the combination with the screw spindle and disk provided with ratchet teeth,

of an arm loosely mounted upon the spindle,

a, pawl upon the arm and engaging the ratchet teeth, and means for reciprocating the arm.

4. In a micrometric feed for a grinding machine the combination with the screw spindle and disk provided with ratchet teeth, of an arm loosely mounted upon the spindle, a pawl upon the arm and engaging the ratchet teeth, and means for reciprocating the arm a varying distance.

5. In a micrometric feed for a grinding machine the combination with the screw spindle, toothed disk, and operating lever, of an arm upon the spindle, a awl on the arm engaging the disk, a second ever, a link connectingthe second lever to the arm, and means actuated by the operating lever for vibrating the second lever.

6. In a micrometric feed for a grinding machine the combination with the screw spindle, toothed disk, and operating lever, of ancarm pivoted upon thes indle, a pawl upon the arm engagingthe disli, a horizontal lever, a link connecting the horizontal lever to the arm, vertically-adjustable screws in the horizontal lever, a rocking member above the horizontal lever, arms upon the rocking member adapted to contact with the screws, and a link connecting the rocking member to the operating lever.

7. In a micrometric feed for a grinding machine 'the combination with the screw spindle, and toothed disk, of a awl arm pivotally mounted upon the spindle, a pawl upon the arm adapted to engage the disk and provided with interspaced cavities, a slidable pin in the arm ada ted to enter the cavities, and means for vi rating the pawl arm.

8. In a micrometric feed for a grinding machine the combination with the screw spindle and disk provided with ratchetteeth, of an arm pivotally mounted upon the spindle, a carrier upon the arm independent of the disk, and pivotal means in the carrier adapted to engage a ratchet tooth and ad- Vance the disk.

9. In a micrometric feed for a grinding to the carrier, a spring arm upon the hand lever, a finger upon the spring arm adapted to engage the ratchet teeth, and an adjusting screw in the hand lever adapted to contact with the spring arm.

11. In a micrometric feed for a grinding mediate its length to the carrier, an-arm upon the hand lever, a finger uponthe arm ada ted to'engage the ratchet teeth and yielding.

means in the carrier for depressing one end of the hand lever.

12. In a micrometric feed for a grinding machine the, combination with the screw spindle, ratchet disk, and means for intermittently rotating the disk of yielding means contacting with the face of the disk for pre ventin over-rotation 13. n a micrometric feed for a grinding machine the combination with the screw spindle, ratchet disk and means for intermittentlf rotating the disk, of an arm loosely mountec upon the spindle, means for locking the arm against movement, a friction late in the arm adjacent the disk, and yielding means in the arm for pressing the plate into frictional contact with the face of the disk,

14. The combination with the frame, screw spindle, ratchet disk, and disk operating mechanism of a grindin machine, of an arm loosely mounted upon t e spindle, frictional means upon the arm contacting with the disk, and means upon the frame for lock ing the arm'against movement.

15. The combination with the frame,

screw spindle, and ratchet disk of a grinding machine, of a carrier armloosely pivoted upon the screw spindle, a carrier upon the arm,

a hand lever in the carrier, an arm on the lever, .a finger on therarrn ada ted'toengage the ratchet disk, and a lock bar pivoted to frame and engaging the carrier.

16. In a micrometric feed for a grinding machine the combination with an arm pivoted to the spindle, a pawl upon the arm engaging the dis, a second lever, a link connecting t e second lever with the arm; a rocking member abovethe second lever, a link connecting the'rocking member to the operating lever, and adjusting means in the second lever contacting with the rocking member. I

In testimony whereof I have afi'ixed my signature in resence of two witnesses.

ARLES G. TREFETHEN.

- W'it'nesses:

HORATIO E. BELLows, Josnrn E. BURNS.

:10 a a screw spin- .dle, toothed disk, and, operating lever, o 

